rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-...!: (1 GPs behind) idle=6ca/1/0x4000000000000004 softirq=11427/11428 fqs=111 (t=10501 jiffies g=11361 q=323) rcu: rcu_preempt kthread starved for 10280 jiffies! g11361 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0 rcu: RCU grace-period kthread stack dump: rcu_preempt I29392 10 2 0x80004000 Call Trace: context_switch kernel/sched/core.c:3254 [inline] __schedule+0x755/0x1580 kernel/sched/core.c:3880 schedule+0xd9/0x260 kernel/sched/core.c:3947 schedule_timeout+0x486/0xc50 kernel/time/timer.c:1807 rcu_gp_fqs_loop kernel/rcu/tree.c:1611 [inline] rcu_gp_kthread+0x9b2/0x18c0 kernel/rcu/tree.c:1768 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 NMI backtrace for cpu 1 CPU: 1 PID: 9867 Comm: syz-executor.0 Not tainted 5.3.0-rc7+ #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x23b/0x28b lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x183/0x1cf kernel/rcu/tree_stall.h:254 print_cpu_stall kernel/rcu/tree_stall.h:455 [inline] check_cpu_stall kernel/rcu/tree_stall.h:529 [inline] rcu_pending kernel/rcu/tree.c:2736 [inline] rcu_sched_clock_irq.cold+0x4dd/0xc13 kernel/rcu/tree.c:2183 update_process_times+0x32/0x80 kernel/time/timer.c:1639 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:167 tick_sched_timer+0x53/0x140 kernel/time/tick-sched.c:1296 __run_hrtimer kernel/time/hrtimer.c:1389 [inline] __hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1451 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1509 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1106 [inline] smp_apic_timer_interrupt+0x160/0x610 arch/x86/kernel/apic/apic.c:1131 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830 RIP: 0010:__list_del_entry include/linux/list.h:131 [inline] RIP: 0010:list_move_tail include/linux/list.h:213 [inline] RIP: 0010:hhf_dequeue+0x5c0/0xa20 net/sched/sch_hhf.c:439 Code: b6 14 20 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 3f 04 00 00 45 0f af b5 14 03 00 00 48 89 df 45 01 fe 44 89 73 10 bb e0 77 fd 31 ff 41 89 c6 89 c6 e8 3f 26 ac fb 45 84 f6 74 63 RSP: 0018:ffff8880ae908e78 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000007 RBX: ffff8880a428e7b8 RCX: ffffffff85c64b39 RDX: 0000000000000000 RSI: ffffffff85c65006 RDI: ffff8880a428e7b8 RBP: ffff8880ae908ec8 R08: ffff88808cda46c0 R09: 0000000000000000 R10: fffffbfff134af8f R11: ffff88808cda46c0 R12: dffffc0000000000 R13: ffff8880a428e4c0 R14: 0000000000000000 R15: 0000000000000000 dequeue_skb net/sched/sch_generic.c:258 [inline] qdisc_restart net/sched/sch_generic.c:361 [inline] __qdisc_run+0x1e7/0x19d0 net/sched/sch_generic.c:379 __dev_xmit_skb net/core/dev.c:3533 [inline] __dev_queue_xmit+0x16f1/0x3650 net/core/dev.c:3838 dev_queue_xmit+0x18/0x20 net/core/dev.c:3902 br_dev_queue_push_xmit+0x3f3/0x5c0 net/bridge/br_forward.c:52 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] br_forward_finish+0xfa/0x400 net/bridge/br_forward.c:65 NF_HOOK include/linux/netfilter.h:305 [inline] NF_HOOK include/linux/netfilter.h:299 [inline] __br_forward+0x641/0xb00 net/bridge/br_forward.c:109 deliver_clone+0x61/0xc0 net/bridge/br_forward.c:125 maybe_deliver+0x2c7/0x390 net/bridge/br_forward.c:181 br_flood+0x13a/0x3d0 net/bridge/br_forward.c:223 br_dev_xmit+0x98c/0x15a0 net/bridge/br_device.c:100 __netdev_start_xmit include/linux/netdevice.h:4406 [inline] netdev_start_xmit include/linux/netdevice.h:4420 [inline] xmit_one net/core/dev.c:3280 [inline] dev_hard_start_xmit+0x1a3/0x9c0 net/core/dev.c:3296 __dev_queue_xmit+0x2b15/0x3650 net/core/dev.c:3869 dev_queue_xmit+0x18/0x20 net/core/dev.c:3902 neigh_hh_output include/net/neighbour.h:500 [inline] neigh_output include/net/neighbour.h:509 [inline] ip6_finish_output2+0xf58/0x2520 net/ipv6/ip6_output.c:116 __ip6_finish_output+0x444/0xa50 net/ipv6/ip6_output.c:142 ip6_finish_output+0x38/0x1f0 net/ipv6/ip6_output.c:152 NF_HOOK_COND include/linux/netfilter.h:294 [inline] ip6_output+0x235/0x7c0 net/ipv6/ip6_output.c:175 dst_output include/net/dst.h:436 [inline] NF_HOOK include/linux/netfilter.h:305 [inline] ndisc_send_skb+0xf29/0x1450 net/ipv6/ndisc.c:504 ndisc_send_rs+0x134/0x6d0 net/ipv6/ndisc.c:698 addrconf_rs_timer+0x30f/0x680 net/ipv6/addrconf.c:3879 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1322 expire_timers kernel/time/timer.c:1366 [inline] __run_timers kernel/time/timer.c:1685 [inline] __run_timers kernel/time/timer.c:1653 [inline] run_timer_softirq+0x697/0x17a0 kernel/time/timer.c:1698 __do_softirq+0x262/0x98c kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x19b/0x1e0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:537 [inline] smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1133 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:768 [inline] RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x95/0xe0 kernel/locking/spinlock.c:191 Code: 48 c7 c0 50 f4 d2 88 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 39 48 83 3d 72 d9 94 01 00 74 24 48 89 df 57 9d <0f> 1f 44 00 00 bf 01 00 00 00 e8 bc a6 10 fa 65 8b 05 0d e3 c3 78 RSP: 0018:ffff888094e77b18 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff11a5e8a RBX: 0000000000000286 RCX: 1ffffffff134b5ce RDX: dffffc0000000000 RSI: ffffffff8177f1ae RDI: 0000000000000286 RBP: ffff888094e77b28 R08: ffff88808cda46c0 R09: fffffbfff11cae6d R10: fffffbfff11cae6c R11: ffffffff88e57363 R12: ffffffff88e57360 R13: ffff8880898e21c0 R14: ffff888094e77bd8 R15: ffff8880a6743cc8 quarantine_remove_cache+0x85/0x100 mm/kasan/quarantine.c:320 kasan_cache_shutdown+0x1e/0x22 mm/kasan/generic.c:203 shutdown_cache+0x13/0x300 mm/slab_common.c:603 kmem_cache_destroy+0x217/0x280 mm/slab_common.c:946 p9_client_destroy+0x24a/0x360 net/9p/client.c:1096 v9fs_session_close+0x4a/0x2d0 fs/9p/v9fs.c:498 v9fs_kill_super+0x4e/0xa0 fs/9p/vfs_super.c:218 deactivate_locked_super+0x95/0x100 fs/super.c:331 deactivate_super fs/super.c:362 [inline] deactivate_super+0x1b2/0x1d0 fs/super.c:358 cleanup_mnt+0x351/0x4b0 fs/namespace.c:1102 __cleanup_mnt+0x16/0x20 fs/namespace.c:1109 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x316/0x380 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline] syscall_return_slowpath arch/x86/entry/common.c:274 [inline] do_syscall_64+0x5a9/0x6a0 arch/x86/entry/common.c:299 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c2a7 Code: 64 89 04 25 d0 02 00 00 58 5f ff d0 48 89 c7 e8 2f be ff ff 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 9d 8d fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffeb105db58 EFLAGS: 00000206 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000000045c2a7 RDX: 0000000000403520 RSI: 0000000000000002 RDI: 00007ffeb105dc00 RBP: 0000000000000029 R08: 0000000000000000 R09: 000000000000000a R10: 0000000000000005 R11: 0000000000000206 R12: 00007ffeb105ec90 R13: 0000555555c58940 R14: 0000000000000000 R15: 00007ffeb105ec90